1. Field of the Invention
The present invention relates to a fuel injection valve, in particular, to a cylinder injection type fuel injection valve. In more particular, it relates to a fuel injection valve of such a type that a swirling energy is given to a fuel stream by means of a swirling means so that fuel is injected through a fuel injection nozzle.
2. Discussion of Background
Heretofore, several kinds of fuel injection valve which inject highly pressurized fuel with high efficiency have been proposed. In particular, a cylinder injection type fuel injection valve of such a type that a swirling energy is given to a fuel stream to inject fuel through a fuel injection nozzle directly into a combustion chamber of an internal combustion engine, has been proposed. Such fuel injection valve is generally provided with an injection valve body comprising a valve (such as a needle valve, a spherical valve or the like) and a valve seat, a housing including a solenoid for operating the valve and a swirler which gives a swirling energy to a fuel stream.
However, publications concerning the proposed fuel injection valves have failed to describe in detail the shapes of the swirler, the valve seat and the fuel injection nozzle. Namely, the publications do not clearly show numerical values and relations of the shapes of the swirler which provides a desired pattern of fuel spray, the valve seat and the fuel injection nozzle. In particular, the publications do not clearly show structures of an injection valve which form a shape of fuel spray or the optimum combustion of fuel in a cylinder type injection engine.